It is a desire of manufacturers of processed tubing to be able to convey the processed tubes from one working station to another without requiring an intervention of personnel to effect the aforesaid transfer. Machinery is already known from U.S. Pat. No. 5,233,853, assigned to the same assignee as is the present invention, for stretch straightening tubing drawn from a reel of tubing, cutting same to a predesignated length and then bending it into a hairpin shape. This particular invention arose out of a need to take the bent hairpin tubes from the apparatus disclosed in the aforementioned patent and deliver it to another station for further processing. In this instance, the further station is a lacing station whereat the hairpin tubes are inserted into a stacked array of thin sheet metal sheets having holes punched therein and axially aligned with one another so as to receive the legs of the hairpin tube therein. Devices for automatically lacing tubing into the thin fins, also known as fin plate, is known from U.S. Pat. Nos. 4,543,711 and 4,584,751. However, it has been problematic in effecting an adjustable transfer of the tubing to cause the lateral spacing between mutually adjacent hairpin tubes to be adjusted so as to accommodate varying lateral spacing between axially aligned sets of holes that have been prepunched into the thin sheet metal fins.
Accordingly, it is an object of this invention to provide a tube transfer device wherein sections of tubing are conveyed from one station to another while simultaneously altering the lateral spacing between mutually adjacent tubes.
It is a further object of the invention to provide a tube transfer device, as aforesaid, wherein the transfer is effected without the intervention of personnel assisting the transfer.
It is a further object of the invention to provide a tube transfer device, as aforesaid, wherein the transferred tubes are delivered to a lacing station whereat the tubes are laced into prepunched holes provided in a stack of thin sheet metal fins.
It is a further object of the invention to provide a tube transfer device, as aforesaid, which is part of a system employed for manufacturing heat exchangers.
It is a further object of the invention to provide a tube transfer device, as aforesaid, wherein the tubes are bent into a hairpin shape and the legs thereof are forcibly guided by a mechanism into axially aligned holes prepunched into the stack of thin sheet metal fins.
It is a further object of the invention to provide a tube transfer device, as aforesaid, wherein the forcible guiding of the legs of the hairpin tubes includes structure for facilitating the removal of a section of the guide to facilitate the movement of the 180.degree. bend interconnecting a common end of each of the mutually adjacent legs of the hairpin tubes past the guide structure and toward the endmost sheet of the stack of thin sheet metal fins.
It is a further object of the invention to provide a tube transfer device, as aforesaid, which is durable and easy to maintain and inexpensive to operate.